If you want to be active start running. It doesn't take much and it is available anywhere you go. You can run outside,  in a woods, through neighborhoods, on trails, on treadmills and bunch of other machines that offer similar movements as running, you can do it in a swimming pool etc. It's a great exercise, which can be a social event or more meditation oriented activity if you prefer it that way. You can do it anytime during a day and it doesn't require much: a pair of (good) running shoes, everything else is optional. 

I started running in 2004 as a part of my workout warm-up routine. At that time it was more a result of a need to do something for my health than anything else. A good year later running started becoming more and more important part of my exercise and I even started entertaining idea to run a marathon once in the future. In late 2006 I set a goal; to run the Boston marathon in 2008. (I never qualified for that year but I have got much better than I used to be. Maybe I'll run Boston in 2010.)

In the middle of 2007 I prepared 16-week training plan and stick with it most of the time. On October 28, 2007 I finished my Marathon 1. The feeling was sensational despite awful pain that would not go away for days. Since than I've run few more marathons and it has become much easier in physical sense but it still feels awesome every time I do it.

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